I don't think its a sticky key. I think its contact is worn out. There is no consistency as to whether it will turn on or not. Today is a good day and I just have to press the button lightly to turn it on. Yesterday no matter how hard or soft I pushed it it wouldn't turn on and I had to resort to using the Windows calculator (oh the horror). I am a heavy calculator user so not having my favorite hefty calculator at hand puts me out of sorts.

On a side note, I actually have to keep 2 calculators at hand. I keep looking to see if anyone has written an HP calculator program that will do foot/inch/fraction units so I can get rid of my little foot/inch calculator, but so far I haven't found a program to do that. That's a program I'd pay money for. Sadly not even the new HPs have that functionality or programming available.